

A036260


Numbers k > 1 such that k mod ord2(k) is even, where ord2(k) is the order of 2 mod k.


3



2921, 3017, 3473, 3479, 5767, 5969, 6167, 6377, 6497, 6913, 7223, 7519, 7567, 7751, 9017, 9271, 10199, 10447, 11431, 11929, 12719, 13439, 13609, 14513, 16583, 17009, 17143, 18631, 18809, 19313, 20737, 21119, 22337, 22351, 22537
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OFFSET

1,1


COMMENTS

These are all composite since for prime p, ord2(p)  phi(p) = p1, whence p mod ord2(p) = 1.


LINKS



MATHEMATICA

Select[Range[3, 23000, 2], EvenQ[Mod[#, MultiplicativeOrder[2, #]]] &] (* Amiram Eldar, Jul 30 2020 *)


CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS



STATUS

approved



